class HumenChild {
    public name: string;/*公有属性*/
    constructor( name: string ) {
        this.name = name
    }
    run(): string{
        return `${this.name}在运动`
    }
}

class Child extends HumenChild{
    constructor( name: string ) {
        super(name)
    }

    work() {
        console.log(`${this.name}在工作`);
        
    }
}

let w = new Child( '李四' )
w.work()//李四在工作